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Phases in development of a small wind electric generator has been explained. Design and Construction of ' blades Is given in some detail. An approach to design of furling unit has been proposed and tried. Wind tunnel tests and field trial results have been included

Accumulation of large quantity of non-biodegradable textile dyes into the environment made much attention to finding a suitable solution for the degradation of textile dyes. In this present study, decolorization efficiency of two different treatment technologies such as Photo-Assisted Chemical Oxidation (PACO – UV/H2O2) and Electrocoagulation (EC) on Reactive Blue 194 dye solution (RB194) at different operational conditions were analyzed and the competitiveness of the treatment technologies in terms of energy consumption and operational costs were discussed. Even though both the processes follow different mechanistic approach for the degradation of dye solution, both the processes achieved more than 99% of decolorization efficiency. In terms of material/chemical consumption for the decolorization of dye solution PACO (US$ 0.016) competes with the EC (US$ 0.5937). But in terms of electrical energy consumption as well as the overall operating cost EC process compete (US$ 0.0481 & US$ 0.6418) with the PACO process (US$ 1.0267 & US$ 1.04337).

In the vast expanse of the Universe and on our planet, nuclei exist in a state of excitement. These excited nuclear states (isomers) can persist for varying periods, from fractions of a second to billions of years and beyond, before decaying to their ground state. If harnessed, feeding and depleting these isomers could represent a clean and high-density way to store and release energy on demand. The quest for efficient dynamical population control of nuclear isomer has long captivated the imagination of physicists, yet this elusive goal remains beyond our grasp. In this dissertation, I examine the potential of employing nuclear excitation mechanisms as viable tools for achieving such manipulation. Three processes of nuclear excitations from both theoretical and experimental perspectives are explored: direct photoabsorption, nuclear excitation by electron capture (NEEC), and nuclear excitation by free muon capture (NEuC). This thesis begins by delving into the historical framework of nuclear excitation by electron capture (NEEC), a process that was proposed in 1976 and is yet to be comprehended. A recently claimed observation has sparked new interest in nuclear excitation processes as a way to release the energy trapped in isomers. However, the irreconcilability between the first observation, the theoretical framework, and the recent repetition of the experiment reveals that there is still much to learn. Regardless of the specific process being examined, the primary goal is to increase the likelihood of their occurrence. One such possibility involves NEEC taking place in excited ions, where the screening effect of other electrons provides nearly resonant orbitals where capture can occur. This process was initially proposed to mitigate the discrepancy between the experimental finding and the theoretical prediction. In this new setting, three orders of magnitude increase in the NEEC cross-sections for 73Ge is found theoretically. Another approach enabling the manipulation of the NEEC cross-section involves engineering the electron wavefunction that undergoes capture. This technique not only demonstrates an increased occurrence of NEEC but also highlights the potential to alter the shell where the highest capture takes place. The second mechanism, NEuC, occurs in exotic muonic atoms. The process is introduced as a counterpart to NEEC, with the electron being replaced by a muon. It follows a presentation of the framework within which this process has emerged and how it changes the paradigm in comparison to NEEC. Owing to the increased proximity of muons to the nucleus, this process has been found to exhibit cross-sections that are several orders of magnitude higher than NEEC for excitations in the MeV range. By examining the unique properties of NEuC, insights into the process and its potential applications are provided, including muon-induced fission. Lastly, nuclear excitations are studied in the context of a laser-generated plasma scenario, where nuclei might be excited through the resonant absorption of a photon, together with other competing processes. The design and implementation of a tabletop setup for generating keV-hot plasma upon femtosecond laser irradiation are presented. The experimental work has been conducted on a 181Ta target using a time-dependent X-ray spectroscopic technique. The absence of a clear decay signal raises the question of whether the excitation of the 181mTa isomer has ever been observed in this context.

In the present study, ultra low carbon steel samples were deformed in near plane-strain mode with different strains, strain rates and temperatures. Estimates of in-grain misorientation developments were obtained respectively for the gamma-fiber (ND//) and alpha-fiber (RD//) oriented deformed grains. Though a general drop in in-grain misorientation was observed with increase in deformation temperature, the highest reduction of 70% showed a clear increase at the intermediate deformation temperatures. Under these condition(s), the misorientation increase in deformed gamma-fiber grains was more substantial than in alpha-fiber grains. The phenomenon was related to the preferred appearance of grain interior strain localizations. The study brings out a clear possibility of optimizing the stored energy advantage in the deformed gamma-fiber through controlled warm working.

The main research question in this research project is: What are the essential elements and the organizing logic of an integrative framework that is suitable for analysing sustainability governance from a global perspective and for implementing the related transitions? This transdisciplinary research approaches this question from three main avenues. First, the research is based on the premise that applying a combination of innovative governance theories is needed in order to improve the analysis of sustainability governance. Secondly, this research explores the interests of core actors in one ‘lay of the land' study on climate governance and in two unique case studies on ‘globalisation of sustainable energy technologies' and ‘aviation and climate change'. Thirdly, the research draws inferences on some areas in which the study and practice of sustainability governance need to be expanded. The findings together form the basis for a new approach to sustainability governance: Integrative Sustainability Governance (ISG). The ensuing ISG framework includes indicator frames within the theoretical pillars of power, knowledge and norms. Other main findings are that the transformation of crisis into transitions needs to find a place in risk management; that systems deliberation can complement democracy in addressing wicked problems; and that insights from behavioural science can play a crucial role in successful transitions. This dissertation concludes by demonstrating the applicability of the findings to ‘SDG Hubs' or innovative platforms for collaboration and knowledge exchange on the 2030 Agenda for Sustainable Development.

Forestry-drained peatlands in the boreal region are currently undergoing restoration in order to bring these ecosystems closer to their natural (undrained) state. Drainage affects the methane (CH4) dynamics of a peatland, often changing sites from CH4 sources to sinks. Successful restoration of a peatland would include restoration of not only the surface vegetation and hydrology, but also the microbial populations and thus CH4 dynamics. As a pilot study, CH4 emissions were measured on two pristine, two drained and three restored boreal spruce swamps in southern Finland for one growing season. Restoration was successful in the sense that the water table level in the restored sites was significantly higher than in the drained sites, but it was also slightly higher than in the pristine sites. The restored sites were surprisingly large sources of CH4 (mean emissions of 52.84 mg CH4 m(-2) d(-1)), contrasting with both the pristine (1.51 mg CH4 m(-2) d(-1)) and the drained sites (2.09 mg CH4 m-(2) d(-1)). More research is needed to assess whether the high CH4 emissions observed in this study are representative of restored spruce mires in general. Peer reviewed

We report on an in situ high resolution core level photoemission study of the early stages of interface formation between an ultrathin SiOx layer ( ∼ 0.3 nm) grown on the atomically clean Si(111) surface and a HfO2 dielectric layer. Si 2p core level spectra acquired at 130 eV photon energy reveal evidence of a chemically shifted component on the lower binding energy side of the substrate peak which is attributed to interface defect states resulting from the incorporation of silicon atoms from the substrate into the interfacial oxide at room temperature. This evidence of Si/SiOx interface disruption would be expected to increase charge carrier scattering mechanisms in the silicon and contribute to the generally observed mobility degradation in high-k stacks with ultrathin silicon oxide interface layers.

Hydropower plants (HPPs) can block or delay fish migration and cause fish injuries or mortalities during the turbine passage. As a consequence, fish populations in many fresh water systems decline. Mechanical and behavioral Fish Guidance Structures (FGS) with vertical bars and large bar spacing are effective solutions to protect and guide downstream migrating fish at water intakes of medium-to-large HPPs (Bates & Vinsonhaler, 1957; Electric Power Research Institute [EPRI] & Dominion Millstone Laboratories [DML], 2001; Amaral et al., 2001 and Boes & Albayrak, 2017). However, the current design of such FGSs, namely louvers, angled bar racks and modified bar racks (MBR) leads to high head losses and unfavorable upstream and downstream flow fields, which are critical factors for their successful implementation at HPPs. In the scope of the EU Horizon 2020 research project “Fishfriendly Innovative Technologies for hydropower” (FIThydro), we have developed two innovative curved-bar shapes for FGSs, assessed their hydraulic performance for a range of parameters and developed a hydraulic head loss formula. In this paper, we give a short introduction on the current and new bar design of FGSs, present the classic trash rack formulas and the new head loss formula for FGSs and their application for two Swiss HPPs, discuss the results and draw conclusions.